This video is an excellent example of how science and art can be combined to make something extremely visually appealing. In this video, the Slow-Mo Guys (Daniel Grunchy and Gavin Free) take a non-Newtonian fluid made from cornstarch and water, and put some of it on a speaker. They then run audio through the speaker and record the motion of the fluid with a slow-motion camera.
This is a great example of science in the sense that we can see how non-Newtonian fluids behave under stress. Non-Newtonian fluids do not follow Newton’s law of viscosity. When shear stress is introduced to the fluid, the viscosity of the fluid changes linearly with the amount of stress applied to it. In this video, the stress applied to the fluid is the normal force from the speaker as well as some shear force from the outer edges of the speaker where the speaker is curved. The combination of these forces changes the viscosity of the fluid, making it almost behave like a solid material, bouncing off the speaker as it is playing. Once the speaker is turned off, the stress on the fluid also goes away, and the once blob-like fluid returns to a fluid-like state.
Watching the physics of the non-Newtonian fluid at play is an art of itself. Because the Slow-Mo Guys recorded at an extremely high frame-rate, the fluid appears to bounce around like a ball on the speaker while it is running. The random strings of fluid that appear to separate from the large portion of the fluid are visually pleasing to watch in slow motion, as they fly around in the air, eventually re-connecting with the central mass or flying out of the camera’s view.
Video Credit: The Slow-Mo Guys (Daniel Grunchy and Gavin Free) https://www.youtube.com/watch?v=RkLn2gR7SyE?rel=0